The disclosed embodiments of the present invention relate to a package on package (POP) structure, and more particularly, to a POP structure including at least a first package and a second package connected to each other via a plurality of pillar bump pins, and related method thereof.
Package on package (POP) is a widely applied integrated circuit packaging method for combining vertically discrete logic and memory ball grid array (BGA) packages, wherein two or more packages are installed atop each other, i.e. stacked, with a standard interface to route signals between them. This allows higher component density in devices, such as mobile phones, personal digital assistants (PDA), and digital cameras.
Configurations for POP such as pure memory stacking and mixed logic-memory stacking are commonly applied in systems having size requirements, e.g. a mobile phone. However, the conventional BGA employed for combining packages to form the POP stacking structure has its restrictions with pitch width. In other words, the pitch width of BGA is hard to be reduced and may lead to inadequate pin count between the stacked packages, which contradicts the trend of growing density of memory and logic dies.